Explosive.



Unw ap orafrns HANS VON DAHMEN, OF VIENNA,

Eatented. September 13 190%.

PATENT @rricn.

AUSTRIA-HUNGARY, ASSIGNOR TO PLQSWE.

SPEGIFIGATION formingpart of Letters Patent No. 770,047, dated September 13, 1904.

Application filed April 12, 1904' Serial No. 202,778. (No specimens.) 7

To all whom it Jnwy concern:

Be it known that I, Hans VON DAHMEN, a subject of the Emperor of Austria-Hungary, and a resident of Vienna, in the Empire of Austria-Hungary, have invented new and useful Improvements in Explosives, of which the following is a specification. I

A serious inconvenience attaching to explosives of the nitrateof-amnionium group is that they are extremely insensitive and very heavy and can usually only be brought to explosion by the aid of very strong fulminate of -mercury preparations. On being compressed even only to a relatively small extent this drawback becomes still more pronounced, inasmuch as most ammonium-nitrate explosives are thereby rendered absolutely insensible-that is to say, they cannot be detonated at all. Even in mining this peculiarity is a frequent cause of misfiring. For artillery purposes such explosives, despite the excellent qualities they possess in other respects, are altogether unusable, as the compression in the hollow projectiles on firing and on striking or grazing is enormous. After exhaustive study I have succeeded in overcoming these defects.

My new process is. applicable to all those ammonium-nitrate explosives one or more components of which are fusible, the fusingpoint being below the point of decomposition ,of ammonium nitrate. All solid fusible n1trohydrocarbons l lind to be particularly suitable, especially if they are added to the explosive known under the name ammonal and consisting of ammonium nitrate, rod hydrogenous charcoal, and aluminium.

In carrying out my process 1 proceed as follows: The ingredients of the explosives are submitted to very fine division and extremely intimately i'ncchaiiically mixed, whereupon the mixture is pressed into cylindrical form under a pressure of one thousand to live thousand kilograms per square centimeter. 'lhc cylinders are then introduced into a heatingapparatus and exposed to a temperature which is only a few degrees below the fusing-point of the fusible romponrnts. The duration of this treatment is i-ltllllllllllkl ex wrimmnally.

I The heating must be continued until the whole cylinder, including the interior, is of the temperature indicated. Thereupon theheated cylinders are placed on --wir'e-netting and im- "nrerse'd"'iifi b atli consisting of the same fused substance as the fusible component. The bath must be of suificient depth to permit of the cylinders .being wholly immersed. As owing to the preliminary heating operation the diii'erence between the temperature of the cylinder and that of the fused mass in the ponents in the cylinder Will take place very rapidly. The cylinder Will expand both longitudinally and laterally without losing its shape in any way. After a certain time (which must be determined experimentally in each particular instance, since the action in any given case is dependent upon thedimensions of the cylinder) the cylinder must be removed, wiped, and exposed to a current of air or the like to cool it. The cooling operation results in rapid contraction, to which, however, only the fusible component, but not the solid ingredients, is subject, whereby at every place where even only the smallest particle of the fusible component has been lying a hollow space is formed, which space is admirably adapted to propagate the wave of, explosion. The increase in diameter, as well-as in height, of such a cylinder is remarkable. The enlargement, according to actual experiments, is on the average about two to three per cent, the bath being heated to its natural fusing-point. If, however, the temperature of the bath be raised further, the expansion of the cylinder increases, and with this enlargement the detonative capacity increases, whereas when the bath is heated only to fusing-point and the cylinder has been suitably heated beforehand scarcely any loss fwcight takes place, providing that the duration of the bath properly selected. This loss of weight is increased on elevation of the temperature of the bath without. however, the increase of the uctonativc capacity hrin, affected; E presented of regulating tln 'dotonativc capacl ity of therxplosivcs.

In this manner the possibility is bath is but slight, fusing of the fusible com- The following example will serve to practically illustrate the procedure.

I first finely divide the following ingrc= dients: ammonium nitrate, forty-seven per cent; red hydrogenous charcoal, one per cent. di or tri nitrotoluene, thirty per cent; aluminiumi twenty-two per cent; total, one hundred per cent. 1 then mingle extremely in timatel and form cylinders thereof by application of pressure of live thousand kilograms I per square centimeter, whereby a density of about 1.9 is attained These cylinders I then heat, as above described, to about 67" centigrade, and when uniformly heated throughout 1 immerse them in a bath of fused di or tri nitrotoluene. As already stated, the duration of immersion will depend upon the dimensions of the cylinder. Supposing the latter, for 1 example, to be eight centimeters high and twelve centimeters in diameter and the bath at a temperature of 90 centigrade, the immersion may occupy about eleven minutes. I then rapidly remove the cylinders from the bath, wipe them, and quickly cool in a current of cold air. if measured, it will be found that 5 the diameter in the case of the above mixture will have increased by about three millimeters and the height by about 2.5 milliu'ietcrs.

If a cylinder is broken up prior to imniersion in the bath, it will be found to consist of a uniformly extremely dense mass, Whereas if a cylinder is crushed subsequent to immersion it will exhibit a mass of hollow spaces.

Such immersed cylinders in projectiles do not in any Way become further conso'iidated or compressed, even with initial velocities oi eight hundred meters, so that their capacity of detonation cannot be altered.

The advantages attaching to my process may be summed up as follows: lirst, considerable reduction in volume, which, especially in the case of shells, is a point of much importance, since they can be charged with larger quantities of explosives than is at pres cut the case, so that the effect is greater; second, misl'iring owing to compression is absolutely avoided; third, hygroscopicity is enor mously reduced; fourth, detonative capacity can be regulated.

I'iaving thus described my invention, what .l claim is'- The process of treating ammonium-nitrate explosives containing a component whose fusing-point is below the temperature of decoruposition of ammonium nitrate, consisting; in

compressing the finely-divided, intimatelymixed components, heating the so-compressed mass, immersing it in a bath of the fusible component in a state of fusion, and finally allowing the mass to cool, substantially as and for the purposes described.

in testimony that I claim the foregoing as my invention i have signed my name in presence of two subscribing WitIlCSSCS.

HANS VON [)AHM EN.

Ni tnesses Wotnmnm lhur'r, Jinx er I iASll-E 1:. 

